Insulated piston



April 12,1927. 1,624,791

M. E. KRAXBERGER INSULATED PI STON Filed Nov 18, 1924 2 Sheets-Sheet 1 FigtIlI A TTORNEY.

April 12, 1927.

M. E. KRAXBERGER INSULATED PI STON Filed Nov. 18, 1924 2 Sheets-Sheet 2 r 1 ENTOR.

ATTORNEY.

l l i Til) Patented Apr. 12, 1927.

MICI'IAEL E. C 13 BUGKINGHAM, COLUILAIJQ.

INSULATED PISTON.

Applicatioii filed November 18, 1924. Serial No. ."IIKLGSO.

This invention relates to pistons and par ticularly to pistons used in internal com bustion engines and has lor an object to prevent inipairn'ient of the crank case lubri cant by heat of the piston head.

A. further object is in an internal combuslion engine, to provide means to prevent crank case luliiricant coming in contact with the piston head.

A further object is, in an internal combustion engine, to provide thermal insulation between the piston head and the crank case lubricant.

A 'l'urlhcr object is lo provide a partition adapted to be readily installed. in a piston ol ordinary types in internal combustion engiru-w, and ada 'il'ed, when so installed, to prevent the crank case luln'icant coming in contact with the piston head.

With these and other objects in view, as will hereinafter more fully appear, the invention comprises certain novel. constrlm tious, combinations and arrangements of parts as and as drawing indicate which .Iligurt-s I is a view looking into the open end of a piston of common form but showing a partition installed therein in accordance with this invention.

Figure II is a longitudinal section taken at line riai of Figure I.

Figure III is a vertical, longitudinal view of another common form of piston showing a. partition installed therein according to this invention.

Figure IV is a horizontal section taken on line b--b of Figure III.

F igure V is a view similar to that in Figure IV but showing a different construction of partition for installation in a piston oi the type shown in Figures III and IV.

Figure VI is a reduced view showing one member oi? the partition as used in. construction illustrated in Figure V.

Figure VII is a reduced view showing one member of the partition as used in Figures I to IV both inclusive.

Figure VIII is a detail view taken on line c- Figure V through the locking indentations.

Figure IX is a longitudinal section of a piston with a modified form of the invenwill now be more fully described illustrated in the accompanying in which like reference characters like parts throughout and in .181 and XI, this view being substantially the same in both of said forms.

In. Figures I to VIII both inclusive, the invention is illustrated as installed in pistons oi types now in common use, while in Figures IX. to XII the illustrations show pistons constructed with a view to installing this invention. V

'lhepiston in all figures has the usual head I, walls 2, ring grooves 3, wrist pin 'bm-rrings a and l'lbS 5.

In Figures I and II there is shown a pis ton of a common design. having a shoulder (S and in this type of piston this invention can be most readily installed. For such a piston I provide two members 7 and 7 shown in detail at Figure VII, member 7 having depending ears 8 for fastening to the walls of the piston in any approved manner as by riveting as illustrated at 9. These two members 7 and 7 are as illustrated circular with oppositely disposed notches E25 and being placed in coincidence, are slid into the piston the notches 2525 clearing the wrist pin bearings l as shown at Figure I, and thereafter member 7 is revolved to dotted line position whereupon the two members form a partition, within the piston, which partition is then pressed against shoulder 6 as clearly shown at Figure II and there secured by suitable means as riveting,

all as illustrated at Figures I and II and as above mentioned.

The partition thus placed prevents the lubricant in the crank case from coming in contact with the head of the piston and thus, when said head is sufficiently hot to Carbonize or otherwise impair such lubricant, the partition prevents the lubricant becoming carbonized or otherwise impaired by contact with the heated piston head.

In Figures III, IV and V there is shown a type of piston in common use having reinforcing ribs extending longitudii'ially of the piston from the wrist pin bearings and necessitating a modifieatioi'i of the partition members and the method of installing the same.

In Figures III and IV partition members 7 and 7" are used but th ears 8 are omitted. By any suitable appliance slits III. are cut in the ribs 10. Members 7 and T are pivotally attached together as by rivet l2 and. are placed in coincidence and slid into the piston past the wrist pin bearings in the same manner as already described. lVllQll opposite the slits 11, the members 7 and 7 are relatively revolved to positions shown by solid and dotted lines Figure IV, one ofthe members 7 or 7 being slid into the slits 11 as clearly shown at Figure III. The partition is thus held in position without other fastening means.

In Figures V, VI, and VIII there is illustrated a modified adaptation of the invention to the construction of piston shown in Figures III, IV and V. The construction and installation are thesame as last above described except that in this modification no slits are out in the ribs 10 but instead thereof the members 7 and 7 are notched as at 13 to accommodate and fit snugly around the ribs 10 when the members 7 and 7 are spread apart all as clearly shown at Figure V. Also in this modification suitable means are provided for normally holding members 7 and 7 in spread position as shown in Figure V which means may consist of dents 14 and 15 in members 7 and 7 respectively which register and interlock'as clearly shown at Figure VIII when members 7 and 7 are spread to positions shown at Figure V.

As clearly shown at Figure III the edges of ribs 10 converge as they extend downwardly so that the edges 13 of the cut outportions of members 7 and 7 will rest against and wedge between the ribs 10 and the partition will thereby be held in place. Ears and rivets may also be provided as in modification in Figures I and II if desired for more Securely holding the partition.

lVith slight change from the ordinary form the piston may be constructed especially for the installation of this invention as illustrated in Figures IX to XII both in elusive.

In Figure IX the piston illustrated is of a common type except that a rim 16 is formed therein leaving an opening which may be stopped by the cap 17 pressed thereinto, in the manner of caps in common use for stopping one end of tin cans and other receptacles. The cap forms a partition to prevent the crank case lubricant coming in contact with the piston head and also forms a sealed air chamber 18 which constitutes thermal insulation tending to prevent transmission or radiation of heat from the piston head toward the crank case and lubricant therein.

In Figure X a partition and sealed air chamber, :l'or like purposes, are illustrated as constructed in a modified form. In this modification the piston is constructed with two annular rims 19 and 20, the latter being of greater width and between these rims a partition .Zl of suitable heat insulatii'ig material. as asbestos, placed resting against rim 20. and being held in position by split ring 22, resting upon rim 19. This modification is somewhat more eilicient as a heat insulator by reason of the combination of the sealed air chamber with the partition of insulating material.

In l igure XI a modification is illustrated in which the sealed air employed as an insulating agent in other modifications, is replaced by other insulating material, as asbestos, packed, into the piston. beneath the head as at 23 and held in position by me1nber 21 which rests upon split ring 22 which in turn rests upon rim 1.) formed integral with the piston. In this constructiol'i ring in'elei'alily has an upturned edge 25 for more securely holding member 2 1-.

The method of installation of the partition 12], ring 22, insulation 23 and member 24; is obvious to one skilled in the art.

It will be obvious that all of the illustrated modifications of this invention will prevent the crank -ase lubricant coming in contact with the piston head within the piston and it will also be obvious that said modilicz tions, in various degrees will insulate and protect the crank case lubricant from the heat of the PISLOII head and from carbonization and other impairment caused by the heat from the piston head.

lVhat I claim is: r

1. rurauxiliary partition for pistons comprising two comglen'ientary parts. pivotally secured together adapted to be ar 'anged to constitute in one position a complete partition and in another position to overlap to permit insertion into the piston.

2. An auxiliary partition for pistons comprising two complementary parts pivotally associated and means for securing said parts against rotation with respect to each other at a predetermined position.

3. in auxiliary partition for pistons comprising two smaller and circular pieces having oppositely d sposed notches adapted to provide a clearance for passage over wrist pin bearings in the piston, and means for securing: said pieces in non-rotative position within the piston.

In testimony whereot I ailix my signature.

.IICIIAEL E, KRAXBERGER.

Ill) 

